Soil resistant carpet fibers



United States Patent 3,159,502 5911.. filSTANT CARPET FllElERS Bernard Menin, Philadelphia, Pa, assignor to E. F. Houghton 8; $0., Philadelphia, Pa, a corporation of Penns lvania No Drawing. Filed July 16, 1962, Ser. No. 210,178 11 Claims. (Cl. l17121) The present invention relates to providing fibers used in carpets and rugs with improved resistance to SOIllIlg, and to a process for imparting soil resistance to such fibers. More particularly, this invention relates to the use of cerain cationic surface-active agents to impart soil resistance to carpets and rugs.

The retardation of soiling of carpeting has been a problem of long standing to the carpet industry. Soil is deposited on carpets during use, and with the more recent advent of wallato-wall carpeting and the use of carpets of relatively light colors, the soiling problem has been greatly emphasized. Attempts to reduce soiling have involved the application of colorless inorganic fine solid particles, such as colloidal silica, to carpeting. These particles serve to fill in voids on the surface of the fibers thereby preventing entry of soil. Unfortunately, the particles are effective only against dry soil, and because they are abrasive in nature tend to reduce the useful life of the carpet.

It is a principal object of this invention to provide a process for treating various fibers used in the resilient floor covering art which markedly increases the soil resistance of the fibers, thereby increasing the useful life or" the Woven product.

i It is another main object of this invention to provide synthetic fibers used in rugs and carpeting with reduced friction properties and improved soil resistance.

A further object of the invention is to provide a method of imparting to finished carpeting Wet and dry soil resistance without resort to the use of abrasive materials.

These and other objects will become apparent from a consideration of the following specification and claims.

According to this invention natural and synthetic fibers suitable for use in carpeting, are treated with certain cationic surface active agents, defined more fully hereinafter, in an amount to impart soil resistance to the fibers. The fibers to be treated can be contacted in the manufacturing of the carpeting, or the fibers of the woven product can likewise be treated.

It has been found that certain cationic surface active agents described below impart unobvious and unexpected anti-soiling properties to the various carpet fibers to which they are applied without adversely affecting the desirable physical characteristics of the fibers, and further, that the anti-soiling properties provided by these compounds are unexpectedly superiorto those of other anti-soilants known previously.

Since these agents are free from oil, they do not readily bind dry soilants such as dust or dirt to the fibers, so that by simple vacuuming operations dry soil particles are readily removed from the carpet fibers. Unlike inorganic powders, such as colloidal silica, which have no beneficial effect in resisting wet-soilants, the anti-soilants used in this inventionare repellent to water or Water base soilants. It has been found, for example, that applying the anti-soilant to the surface of a carpet imparts soil resistance to the fibers thereof so as to effectively resist soiling by beverages such as tomato juice, grape juice, cola, etc.

3,159,502 Patented Dec. 1, 1964 The soil retardant compositions for use in the present invention advantageously are water dispersible. Thus, they can be shipped in either a paste or concentrated liquid form and be subsequently readily diluted with water prior to use. Since they are dispersible in water, the application of these anti-soiling agents to carpeting can be readily accomplished for example by various rug shampooing methods'known in the art.

The cationic surface active agents for use in the invention are carbamide compounds having the following general formula:

wherein R is an alkyl group containing from 12 to 20 car bon atoms, X is an ethylene or propylene group, n is a whole number from 2 to 3, y is a Whole number from 1 to 2, and Z is an organic acid having from 2 to 6 carbon atoms selected from the group consisting of aliphatic carboxylic and hydroXy aliphatic carboxylic acids. The above general formula is referred to hereafter as Formula l.

' The carbarnido compounds of Formula I include tetrahydro pyrimidines and imidazolines. The 1,2-substi-tuted imidazolines, or glyoxalidines as they are often referred to, suitable for use in providing carpeting fibers with soil resistance according to this invention include those having the following general formula:

wherein R, Z, n and y are as defined in connection with Formula I above Typical 1,2-substituted irnidazolines for use in the process of this invention are Z-heptadecyl-l- (Z-carbamidoethylethyl)-irnidazoline acetate; 2-dodecyl- I-(Z carbamidQethyl)-irnidazoline lactate; 2-octadecyl-l- (Z-carbarnidoethyl -irnidazolineoxalate; Z-dodecyl-l- [2- arninoethyl N (2 carbamido propyl)] imidazoline lactate, and 2 heptadecyl 1 [2 arninoethyl N (2- carbarnido propyl)]-imidazoline propionate.

The 1,2-substituted tetrahydro pyrimidines suitable for providing carpeting fibers with anti-soilant properties according to this invention are those having the following general formula:

N-CH:

( n iln y Z (III) wherein R, Z, n and y are as defined with respect to Formula 1 above. Examples of such 1,2-substituted tetrahydro pyrimidines are 2-hexadecyl-l-(2-carbamidoethyl)-tetrahydropyrirnidine propionate; 2-tridecyl-1-(2- carbamidoethyl)-tetrahydropyrimidine lactate; 2-octadecyl-1 (2-carbamidoethyl)-tetrahydro pyrimidine oxalate; Z-heptadecyl-l-[Z-arniuoethyl-N-(Z carmabidopropyl)]- tetrahydro, pyrimidine acetate; and 2-tetradecyl-1-[2-amiuoethyl-N- (Z-carbarnidopropyl) -tetrahydro pyrimidine propionate.

The carbamido compounds of Formula I can be ob- 3 tained by condensing an appropriate fatty acid, fatty acid ester or fatty acid halide with a suitable aliphatic polyarnine, reacting the resulting condensate with urea to obtain a carbamido compound, and converting the resultant carbamido derivative to its corresponding acid salt by the addition of an organic acid.

The acids which may be condensed with polyamines to obtain the carbamido compounds of Formula I, wherein R is defined as having from 12 to carbon atoms, include the following: lauric, tridecoic, myristic, pentadecanoic, palmitic, margaric, stearic, nondecylic, and arachidic acid. Esters and halides of these acids can also be used. Typical examples are the ethyl, propyl and butyl esters, and such halides as chlorides and bromides.

Alkylene polyamines which may be suitably employed as reactants to form the initial acid-amine condensation product are preferably polyalkylene polyarnines such as a dialkylene triamine having the general formula:

wherein n is a whole number from 2 to 3, and y is a whole number from 1 to 2, when n is 2, imidazolines are formed, whereas when n is 3, tetrahydro pyrimidines are formed. Preferred polyalkylenepolyamines are diethylenetriamine, dipropylenetriamine and triethylenetetramine.

The carbamido compound is formed by reacting urea with the 2-alkyl-1-(2-aminoalkyl)-imidazoline or tetrahydropyrimidine formed by condensation of the fatty acid with the alkylene polyamine.

The process of this invention utilizes the acid salts of substituted carbamido derivatives which may be obtained by reacting the carbamido derivatives with an aliphatic carboxylic acid, which may be hydroxy substituted, having from 2 to 6 carbon atoms. For example, low molecular weight, water miscible, mono-, di-, and tri-aliphatic carboxylic acids such as acetic, propionic, butyric, caproic and oxalic acid can be used. Hydroxy derivatives of these acids, such as glycollie, lactic, citric, gluconic and tartaric acids may also be employed.

Fibers which can be rendered soil resistant by the process of the present invention can be natural or synthetic, such as wool and polyamide fibers, respectively. Polyamide fibers, such as those derived from hexamethyl enediamine and adipic acid, and fibers of other synthetic materials such as rayon, Dacron (polyethylene terephthalate), Orlon (predominantly polyacrylonitrile), and blends of such fibers and fabrics containing these fibers or fiber blends are particularly adaptable to treatment by the lubricating, anti-soiling compounds according to this invention.

It will also be understood that while the process of the invention is of particular value in treating synthetic carpeting fibers such as Acrilan and nylon to impart antisoiling properties thereto, it may also be used with advantage in treating other textile fibers and materials, such as cotton, wool, cellulose acetate, etc., due to the desirable anti-soiling properties and, in some cases, improved softening and lubricating characteristics imparted to such fibers by the compounds of Formula I.

The following example illustrates the preparation of a cationic surface active agent for use in the present invention. According to this example a paste dispersible in hot water is formed.

EXAMPLE I Stearic acid (1 mole) was reacted with diethylene triamine (1.1 moles) in the presence of toluene at about 320 F. Water formed by the reaction was removed as formed, and Z-heptadecyl-l-(Z-aminoethyl)-imidazoline, was produced. This compound was isolated and then reacted with one mole of urea in the presence of 0.12 mole of triethylphosphate. The reaction mixture was heated and the ammonia produced was removed. The product formed is 2-heptadecyl-1-(2-carbamidoethyl)- imidazoline.

with water and 0.14 mole lactic acid. The latter formed a salt with the carbamido compound.

The product is a paste-like composition dispersible in hot water. A preservative such as formalin may be added to the paste to increase stability during storage.

Numerous preservatives for cationic surface active agents other than formalin are known in the art and are applicable for use with the anti-soiling agents used in this invention.

Relatively low concentrations in water of the cationic surface active agents of Formula I have been found to give satisfactory results. Such compositions can be applied to the carpeting fibers in any suitable manner, for example by dipping or immersing the fibers in the aqueous composition, by spraying or mechanical application thereof by means of scrubbing or brushing, etc. Such antisoiling composition can be applied to the fibers at any convenient stage of rug manufacturing and finishing, or it can be applied to the finished product by conventional application techniques. Generally, when applied to finished products, such as carpets, the anti-soiling composition also will be in the form of a water base composi tion. When applied to finished fabrics, such as carpets, conventional rug shampooing equipment and techniques may be employed, or the carpeting may be immersed in such a composition containing the anti-soiling compound and then dried in a conventional manner. Such water base compositions may also be applied to fibers in the form of a spray for example, by means of an aerosol bomb.

Satisfactory anti-soiling properties may be imparted to textile fibers according to this invention by applying to the fibers from about 1 to about 6 percent, by weight, of a compound of Formula I, based on the weight of the fibers. Preferably from about 2 to about 3 percent of such a compound is applied. In the case of carpets subjected to heavy traffic and highly soiling conditions, periodic cleaning of the carpets followed by application of the anti-soiling agent should be done to obtain best results.

The effectiveness of the anti-soiling agents of Formula I in imparting anti-soiling properties to carpeting comprising synthetic fibers is illustrated in the following example.

EXAMPLE II In this example the refiectance of a series of Acrilan (a copolymer based on polyacrylonitrile) carpets treated with varying concentrations of the lactate salt of Z-heptadecyl-l-(Z-carbamidoethyl)-imidazoline was measured and compared with a similar untreated control carpet. All of the carpets were subjected to the same usage conditions discussed below.

The cationic surface active agent was prepared as follows: stearic acid (1.0 mole) and diethylenetriamine (1.1 moles) were heated in the presence of toluene to 320 F. with the water of the reaction being removed as formed. Z-heptadecyl-l-(2-aminoethyl)imidazoline was produced.

Urea and triethyl phosphate were then added and the ammonia produced during this portion of the reaction was removed at about 320 F. Z-heptadecyl-l-(Z-carbamidoethyl)-imidazoline was thereby produced. The lactate salt of this carbamido compound was formed by adding 2.5% of a 50% lactic acid in water solution to 30% of the above carbamido compound. A minor amount of formalin was added as a preservative. The resultant product is a paste dispersible in hot water.

Carpets were woven with Acrilan yarn treated with various amounts of the anti-soilant agent produced as described above and these Acrilan carpets were compared with a similar untreated Acrilan carpet. All of the carpets were exposed to extreme soiling conditions by placing them in a highly traveled corridor. Before each daily reflectance reading the carpets were cleaned with a tanktype vacuum cleaner. The percent retained reflectance obtained as above is set forth below in Table I. Original and G subsequent reflectances were determined with a Photovolt Model 610 Reflectometer.

1 After cleaning with rotary brush vacuum cleaner.

On the basis of the retained reflectance values as set forth in Table I above, carpets treated with 6% of the cationic surface active agent according to this invention are soiled the least. The carpets treated with 3% are less soiled than carpets treated with 1 to 1 /2% of the antisoiling agent. The advantages of the invention are clearly illustrated by a comparison of the reflectance values for the untreated carpeting with those of the treated carpeting.

While the invention has been described with reference to various particular embodiments thereof, it is to be appreciated that modifications and variations can be made within the spirit and scope of the invention.

What is claimed is:

1. An article of manufacture comprising a carpeting fiber having on the surface thereof a cationic surface active agent having the general formula:

wherein R is an alkyl group having from 12 to 20 carbon atoms, X is selected from the class consisting of ethylene and propylene, n is a whole number from 2 to 3, y is a whole number from 1 to 2, and Z is an organic acid having from 2 to 6 carbon atoms selected from the group consisting of aliphatic carboxylic and hydroxy aliphatic carboxylic acids.

2. An article of manufacture according to claim 1 wherein said carpet fiber comprises a synthetic fiber.

3. An article of manufacture according to claim 1 wherein said cationic surface active agent comprises 2- heptadecyl-I-(Z-carbamidoethyl) -imidazoline lactate.

4. An article of manufacture according to claim 1 wherein said cationic surface active agent comprises 2- heptadecyl-I-(Z-carbamidopropyl)-tetrahydro pyrimidine lactate.

5. An article of manufacture according to claim 1 wherein the amount of cationic surface active agent on said fiber is from about 1 to about 6 percent by weight, based on the weight of said fiber.

6. An article of manufacture according to claim 1 wherein the amount of cationic surface active agent on said fiber is from about 2 to about 3 percent by weight, based on the weight of said fiber.

7. An article of manufacture according to claim 1 wherein said fibers are in the form of a carpet.

8. An article of manufacture according to claim 1 wherein said carpet fiber comprises a natural fiber.

9. An article of manufacture according to claim 2 wherein said synthetic fiber comprises a polyamide fiber.

10. An article of manufacture according to claim 2 wherein said synthetic textile fiber comprises a polyacrylonitrile fiber.

11. An article of manufacture according to claim 8 wherein said carpet fiber comprises wool.

References Cited by the Examiner UNITED STATES PATENTS 2,176,843 10/39 Kranzlein 260--309.6 2,267,273 12/41 Wilkes et a1.

2,268,276 12/41 Wilson 117139.5 2,355,837 8/44- Wilson.

2,995,520 8/61 Luvisi et al ll 7l39.5 XR

WILLIAM D. MARTIN, Primary Examiner.

RICHARD D. NEVIUS, Examiner. 

1. AN ARTICLE OF MANUFACTURE COMPRISING A CARPETING FIBER HAVING ON THE SURFACE THEREOF A CATIONIC SURFACE ACTIVE AGENT HAVING THE GENERAL FORMULA: 